Cylinders of a web-fed printing press and printing unit

ABSTRACT

A cylinder of a printing unit of a web-fed printing press includes a cylinder channel which receives plate ends and includes plate end retaining devices. A remotely controllable actuating device or an actuator is located in the channel. The actuating device, or actuator is preferably a piezoelectric system or is in the form of a magnetostrictive system. This actuator is usable, preferably during continuous printing, to shift a plate end retaining device inside the channel in an axial direction of the cylinder to achieve an improved register precision and lateral register precision. The device makes it possible to counteract the influence of a transverse strain imposed by the material to be printed and acting transverse to its direction of conveyance, such a transverse strain having an effect on a common printed image that is printed at different positions of the printing unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. patent application is the U.S. national phase, under 35 USC371, of PCT/DE2003/001847, filed Jun. 5, 2003; published as WO2004/018206 A1 on Mar. 4, 2004, and claiming priority to DE 102 36865.1, filed Aug. 12, 2002, the disclosures of which are expresslyincorporated herein by reference.

FIELD OF THE INVENTION

The present invention is directed to cylinders of a web-fed printingpress and to a printing unit. Each cylinder includes at least onecylinder groove that carries an actuator which is usable to axiallyshift a dressing end holding device in the groove.

BACKGROUND OF THE INVENTION

A setting arrangement for use in accomplishing the lateral registrationof printing plates is known from DE 197 57 895 C2. Beveled or anglededges of the printing plates are held in a narrow slit of a formecylinder and each one of the plate edges has a registration cutout, withwhich cutout a registration pin, that is fastened on an axiallydisplaceable insert strip assigned to the latter, can be respectivelybrought into engagement. An end of each of the insert strips is providedwith an adjustment device for use in effecting an axial back-and-forthmovement of each strip. This adjustment device is embodied in such a waythat each insert strip is angled off in an L-shape at one of its ends.The angled piece is fastened to the front end of the forme cylinder bythe use of a screw.

A plate cylinder, with an adjustable lateral registration, is known fromEP 0 229 892 B1. Small register plates are axially displaceable in thecylinder groove by the use of a lateral register adjustment device. Thelateral register adjustment device has rotatable spindles and anadjusting screw.

A device for the correctly registered alignment of a rubber blanket on acylinder of a printing group is known from U.S. Pat. No. 4,707,902.Clamping devices, which are arranged in a groove and which can beactuated by a bracing spindle, can be axially displaced via a manuallyadjustable threaded ring or by an adjustment screw.

A plate cylinder with an adjustable bracing rail is known from DE 42 10897 C1. The adjustable bracing rail, which is arranged in a groove ofthe plate cylinder, can be displaced in a plane via structural rollerring units fastened on the bottom of the groove. Axial displacementtakes place by the use of a pin, which pin engages the underside of thebracing rail and is connected with an eccentric device. The eccentricdevice extends from the interior of the cylinder through the bottom ofthe groove and can be displaced by operation of a gear driven by amotor.

A device for bracing a printing plate on a plate cylinder of a printingpress is known from DE 41 40 022 C2. Clamping devices for the front edgeof the plate and for the rear edge of the plate are situated in anaxially extending groove of the cylinder. The clamping device for thefront edge of the plate can be adjusted in the axial direction of thecylinder by adjustment device. The adjustment device can be displaced byan electric drive motor that is housed in the cylinder. An adjustingshaft of the drive motor projects perpendicularly from the interior ofthe cylinder into the groove. A rotating movement of the adjusting shaftis converted into an axial adjusting movement.

A device for axially positioning a printing plate is known from EP 0 808714 B1. In the course of its mounting, the printing plate can bepositioned with exact lateral registration by the use of an electricalpositioning drive while being moved toward a cylinder.

A device for use in accomplishing the displacement of at least oneregistration element of a printing press is known from DE 101 36 422 A1.In one embodiment of the device, piezo-actuators are provided forposition adjustment. Such a position change takes place in thecircumferential direction.

A device for use in the bracing/clamping of flexible plates with beveledsuspension legs on a printing press cylinder is known from DE 199 24 788A1. Abase body, with bracing and/or clamping elements, which are movablein the base body's interior space, is arranged in a cylinder groove.

A device for adapting the position of printing plates in response todeformation of the paper to be imprinted is known from DE 195 16 368 A1.A position of a punched-out place on a printing plate, which is providedfor receipt of a registration pin, and which is used for accomplishingthe adjustment of the printing plates arranged on a forme cylinder of aprinting press, is adapted to correspond to a lateral extension or fanout of the paper, which fan out is to be expected in the course of thepassage of the paper through a plurality of print positions of theprinting press, which are arranged serially one behind the other.

SUMMARY OF THE INVENTION

The object of the present invention is directed to providing cylindersof a printing press and to providing a printing unit which willcompensate for the lateral extension or fan out of the material to beimprinted.

In accordance with the present invention, the object is attained by theprovision of at least one groove in a cylinder, which is a part of eachone of serially arranged print positions. The groove carries at leastone dressing end holding device that is shiftable over an acutating pathoriented axially in the cylinder by the operation of an acutator. Thatactuator changes its length axially with respsect to the cylinder inresponse to a control signal. Several axially spaced dressings may bearranged on the cylinder and the actuator can be used to change an axialspacing between these dressings. This actuator may be electricallyoperable. When a multi-color image is applied to a web by passage of theweb through serially arranged print positions, the actuators at eachposition can be used to compensate for lateral fan out of the web.

The advantages to be gained by the present invention consist, inparticular, in that it is possible by the accomplishment of a lateraldisplacement of a holding device arranged in the groove, or of a basebody, to align the position, as necessary, of a dressing, which dressinghas been applied to a cylinder and which dressing is held by the holdingdevice, in relation to a material to be imprinted. The material to beprinted is often stretched laterally with respect to the productiondirection, or in comparison with other print positions in the printingunit. Alignment or shifting of the dressing is used for obtaining animproved indexing, as well as for lateral registration accuracy. Thismatching of the dressing position with the lateral web displacement canbe performed by the use of an electrical control signal which can beissued by remote control, from, for example, a control console, duringthe running production process, without it being necessary to stop theprinting unit. The tracking of the print images which are to be broughtinto congruence, can be expanded into an automatically acting controlcircuit, which automatically acting control circuit relieves theoperators from accomplishing this task. Otherwise, the checking of theindexing, as well as the lateral registration accuracy is a task of theoperators monitoring the printing process.

It is particularly effective that it is possible, in accordance with thepresent invention, to arrange the actuating device for use in displacinga holding device, or a base body, integrated into the groove, and inparticular into a cylinder groove that is extending underneath thesurface area of the cylinder. The cylinder groove only has a slit-shapedopening facing toward the cylinder surface area. The integration of theactuating device for use in displacing a holding device, or a base body,in the groove allows such actuating devices to be retrofitted to acylinder that is already in operation, because no extensive interventionis required. By the selection or provision of an appropriate shaping, itis possible to fit the actuating device into the groove in anadvantageous manner.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the present invention is represented in thedrawings and will be described in greater detail in what follows.

Shown are in:

FIG. 1, a schematic depiction of the passage of material to be imprintedextending underneath a cylinder of a printing unit in accordance withthe present invention, in

FIG. 2, a partialsectional representation of a portion of a cylinderwith a groove and with a holding device for a dressing arranged in thatgroove, and in

FIG. 3, a partial cross-sectional representation of an actuator in agroove in a cylinder in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring initially to FIG. 1 and taken in conjunction with FIG. 2, acylinder 01 in a printing unit, such as, for example, a forme cylinder01 or a transfer cylinder 01 in a rotary printing unit, and preferablysuch a cylinder 01 in a printing unit of a web-fed offset printing pressfor newspaper printing, can be provided with at least one dressing 02,as shown in FIG. 2. Such a dressing 02, which may be applied to a formecylinder, can be embodied as a preferably flexible, plate-shapedprinting forme 02, or as a dressing 02 to be applied to a transfercylinder 01, such as a printing blanket applied to a transfer cylinder01. The dressing 02 has suspension legs 06, 07, at its ends 03, 04 whichlegs 06, 07 are beveled. These dressing end suspension legs 06, 07 caneach be inserted into a slit-shaped opening 08 that is located in thesurface area 09 of the cylinder 01, which slit-shaped opening 08preferably extends axially in respect to the cylinder 01. The inserteddressing end suspension legs 06, 07 are preferably held by a holdingdevice, with that holding device being located in a cylinder groove 11.The cylinder groove or channel 11 preferably extends axially, inrelation to the cylinder 01, underneath the surface area 09 of the formecylinder 01 and is accessible through the opening 08. The purpose of thedressing end leg holding device is, inter alia, to fix the dressing 02,which has been applied to the surface area 09 of the cylinder 01 inplace in the axial direction of the cylinder 01. This function can beperformed by, for example, a dressing end holding element 18, that maybe embodied as a registration pin, and which is carried on, or by theholding device.

Advantageously, the cylinder groove or channel 11 can be embodied in theinterior of the cylinder 01 at a radial distance “a” of, for example, 4mm to 10 mm, and preferably of 5 mm, underneath the cylinder surfacearea 09, as a preferably circular bore, and can have a diameter D of,for example from 25 mm to 50 mm, and preferably of 30 mm. A ratio of thediameter of the cylinder 01 to the diameter of groove 11 preferably liesapproximately at 10:1. If the cross-sectional shape of the groove 11 isnot circular, a ratio of a cross-sectional surfaces of the cylinder 01to a cross-sectional surface of the groove 11 is at least 100:1, so thatthe cross-sectional surface of the groove 11 is always comparativelysmall compared to that of the cylinder 01.

Preferably, at least the ends 03, 04 of the dressing 02 are made of ametallic material, such as, for example, an aluminum alloy. Customarily,the thickness M of the material of the suspension legs 06, 07, which arebeveled or angled off at the ends 03, 04 of the dressing 02, is a fewtenths of a millimeter and lies, for example, in a range between 0.2 mmand 0.4 mm, and preferably is 0.3 mm.

It is advantageous to suspend a first one of the suspension legs 06, 07of the dressing 02 in the cylinder 01 from a first opening wall 12 in apositively connected manner. This first opening wall 12 typicallyextends from a first or leading opening edge 13 of the opening 08, whichedge 13 is leading in the production direction P of the cylinder 01, andwhich first opening wall 12 extends from edge 13 toward the interior ofthe groove 11. The angle at the typically leading end 03 of the dressing02 existing between the beveled suspension leg 06 and the rest of thedressing 02, which is stretched out essentially flat on the cylindersurface area 09 preferably corresponds to the angle α which resultsbetween this first opening wall 12 extending toward the interior of thegroove 11, and an imagined tangential line T resting on the opening 08.The other, second typically trailing suspension leg 07 of the dressing02 can also be placed against a second trailing, opening wall 16 in thecylinder 01. This second opening wall 16 extends from a second edge 17of the opening 08, which is trailing in the production direction P ofthe cylinder 01, toward the interior of the groove 11. The angle formedat a typically trailing end 04 of the dressing 02 existing between thebeveled suspension leg 07 and the dressing 02 which is stretched outessentially flat again advantageously corresponds to the angle β whichresults between this second, trailing edge wall 16 extending toward theinterior of the groove 11, and an imagined tangential line T resting onthe opening 08. It is advantageous to make the angle a between 40° and50°, preferably 45°, and to make the angle β between 80° and 95°,preferably 90°. The dressing trailing end suspension leg 07 placedagainst the second, trailing edge wall 16 is preferably beveled at thesame angle β. A bevel of the suspension leg 07 between 80° and 85°, andin particular at 83°, is advantageous. The slit width W of the opening08 is less than 5 mm and preferably lies in the range of between 1 mm to3 mm, so that a ratio of the diameter of the cylinder 01 and the slitwidth W preferably lies approximately at 100:1.

In accordance with a preferred embodiment of the present invention, theholding device arranged in the groove 11 consists of at least onedressing end holding element 18, preferably a dressing end clampingpiece 18, and a spring element 19, wherein a suspension leg 06 or 07 ofthe dressing 02 inserted into the opening 08 is preferably placedagainst the second wall 16 extending from the opening 08 to the groove11 and is pressed against that second wall 16 by the clamping piece 18by a force F which is exerted by the spring element 19 on the clampingpiece 18. A first holding element actuating device, generally at 21 isprovided in the groove 11 for use in releasing the clamping force which,holding element actuating device 21, when actuated, counteracts theforce F exerted by the spring element 19 on the clamping piece 18, andpivots the clamping piece 18 away from the second wall 16 of the opening08. A hose 21 which can be charged with a pressure medium, such as, forexample, compressed air, is preferably provided as the first holdingelement actuating device 21 for actuating the holding device 18 and isadvantageously placed to extend continuously in the groove 11, so thatall holding devices 18 arranged in a groove 11 can be simultaneouslyactuated by the first holding element actuating device 21.

For easier mounting in the groove 11, the holding device 18, togetherwith its first actuating device 21, can be arranged in a base body 22,wherein this base body 22 can be advantageously configured essentiallyas a hollow body, whose exterior contour is essentially matched to thecontour of the groove 11. The base body 22 is preferably supported,fixed against relative rotation, in the groove 11. The clamping piece 18is seated in a pivot bearing 23 in the interior of, or on the bottom ofthis base body 22. It can be advantageous to embody a plurality of thebase bodies 22 as section pieces each of a length l, as seen in FIG. 1of, for example, 30 mm to 100 mm, and preferably of 60 mm, wherein thelength l of an individual base body 22 is short compared to an overalllength L of the barrel of the cylinder 01. Several, preferably identicalbase bodies 22 can be arranged in a row in the groove 11 for use inholding the dressing 02. These individual base bodies 22 can beconnected to each other by couplings which are formed on their front orend faces. For example, these couplings can consist of toothedconnections, tongue-and-groove connections or pin connections

A material 24 to be imprinted in the printing unit is depictedschematically in FIG. 1 and may be, for example, paper 24. Paper 24 is athree-dimensional, hygroscopic material, which changes its shape underthe effects of temperature, humidity and mechanical pressure generatedduring the printing process, by the application of forces acting on thesurface of the paper. Of particular interest in the context of thepresent invention is a lateral extension, depicted by the arrow Q inFIG. 1, of the paper. This lateral extension Q is the so-called fan out,by which is meant a dimensional change of the material 24 to beimprinted, in this case the paper web 24 or the paper sheet 24, whichdimensional change is taken or measured transversely to the productiondirection P of the cylinder 01.

The lateral extension or fanning out Q of the material 24 to beimprinted leads to problems, particularly in a printing unit in whichthe material 24 to be imprinted is to be printed in more than one color.The printing unit, which is not specifically depicted, can be embodied,for example, as a nine-cylinder satellite printing unit, in which fourpairs of cylinders 01, each consisting of a forme cylinder 01 and of atransfer cylinder 01, are arranged in a frame around a commoncounter-pressure cylinder. Each such pair of cylinders 01 constitutes aprint position and prints a definite color, which will form part of thesame printed image, on the material 24 to be imprinted. Even with aprinting unit embodied as a nine-cylinder satellite printing unit, andin which the four print positions responsible for the individual colorsare arranged next to each other in a narrow space, the material 24 to beprinted still travels over a path of up to 1 m in length until all fourcolors for a common printed image have been applied to the material 24to be imprinted. With different configurations of the printing unit, thepath traveled by the material 24 to be imprinted, from the printing of afirst color to the printing of a last color of a common multi-coloredprinted image is even much longer. For example, this path may be longerthan 3 m. The dimensional change of the material 24 to be imprinted,because of the lateral extension or fanning out Q, can becorrespondingly greater and is long-lasting or permanent. If, on its wayfrom one print position to the next, the material 24 to be imprintedchanges in its dimensions transversely to the production direction P ofthe cylinder 01, an inaccurate fit between color points which are to beprinted next to, or above each other, and of which color points theprinted image is composed, results. If this so-called indexing is tooinaccurate, so that the indexing accuracy exceeds a definite toleranceof, for example, 50 μm, the human eye recognizes this indexinginaccuracy, and the quality of the printed image is judged to be bad.Moreover, it is necessary to arrange the printing formes, which arerequired for printing each of the different colors of the same printedimage, on each of their respective cylinders 01 in such a way, that theprinting formes of all of the print positions are aligned with eachother as exactly as possible for forming or producing the common printedimage during the printing process. This is calledthe side and thecircumferential registration accuracy of the printing formes. Inactuality, in indexing, as well as in side and in circumferentialregistration, accuracy of 10 μm and less is currently often demanded.The dimensional instability of the material 24 to be imprinted, which iscausedin particular, by the hygroscopic behavior of material 24, makesit necessary to arrange for the alignment of each of the respectivedressings 02 placed on a cylinder 01, for example each of the printingformes 02, and in particular each of the printed images made by each ofthese printing formes 02, to be adaptable and to be adjustable withrespect to each other during the ongoing printing process.

It is proposed, in accordance with the present invention, to provide atleast one second actuating device 26, which is controllable from outsidethe print position, or from outside the printing unit, and whichpreferably is an actuator 26, which displaces a holding devicedisplaceably arranged for axial movement in a groove 11. By the use ofthis second, laterally operating actuator 26 a dressing 02 is positionedon a cylinder 01, at least in the axial direction of the cylinder 01.The actuator 26 can be configured as a piezo-electric system or as amagnetostrictive system, which actuator 26 is arranged in a housing withan actuator head element 27 and with an actuator base element 28 andwhich actuator 26 has been inserted into the groove 11, typicallywherein at least the base element 28 of the actuator housing is rigidlyconnected with the groove 11. The imposition of an applied electricalcontrol signal, US, causes the head element 27 to make a translatorymovement over a defined actuating path “s,” while the base element 28remains stationary. In this case, the actuating path “s” of an actuator26 can lie in the range of approximately 100 μm. However, displacementsof up to a total of 2 mm can be necessary.

The second actuating device 26, or the actuator 26, preferably perform atranslatory movement in the axial direction of cylinder 01, fordisplacing the holding device 18, or the base body 22, arranged in thegroove 11 in the cylinder axial direction. An actuator 26, which may beembodied as a piezo-electric system, utilizes a so-called indirect piezoeffect, and essentially has a piezo-electrical body made of acrystalline, ferro-electric material, such as, for example, a quartzcrystal, which material is elastically deformed when charged with anelectrical field. If the piezo-electrical body is prevented from beingdeformed, a mechanical stress is created in the crystalline structure ofthe body, so that a force is exerted on the device that is preventingthe body from being deformed. As a rule, charging the piezo-electricbody with an electric field takes place by applying an electric voltageto electrodes which are attached to the piezo-electric body.Analogously, a magnetostrictive system, which may be used as an actuator26, also has a body that is made of a material with magnetic properties,and which uses the physical effect of magnetostriction. This body canconsist of a ferromagnetic metallic material, and wherein this body issurrounded by a coil in order to be able to charge the body with amagnetic field when an electric current is applied to the coil, whichmagnetic field causes the body to become elastically deformed. Thatdeformation of the body can be used to apply a definite exertion of aforce on a device which is connected with the body, if the body of theactuator 26 is firmly clamped on one side. The actuator 26 causes adisplacement of the holding device, or of the base body 22, arranged inthe groove 11, by the body of the actuator 26 being exited to perform achange in its length or shape, wherein the length or shape change of thebody of the actuator 26 is triggered by a control signal US applied toit. A different preferred embodiment can provide a preferablyelectrically operable actuating device or actuator 26, for example anelectric motor arranged in the groove 11, whose effective direction isaxially aligned in respect to the groove 11.

The housing of the actuator 26 can be arranged in the groove 11, forexample, in such a way, in relation to a holding device 18, that theactuating path “s” shown in FIG. 3 caused by the head element 27 of theactuator 26 acts directly on the holding device 18, and the head element27 of the actuator 26 displaces the holding device in a directioncorresponding to the actuating path “s” in the groove 11. If the holdingdevice 18 is arranged in a base body 22, as seen in FIG. 2, and isrigidly connected with the base body 22, the actuating path s caused bythe actuator 26 preferably acts on the base body 22 arranged in thegroove 11. To make a simple matching of at least the head element 27 ofthe actuator 26 to the holding device 18 to be displaced, or to the basebody 22 to be displaced, it is advantageous to match the shape of thehousing of the actuator 26 to the geometry of the groove 11 and, ifnecessary, to match at least the base element 28 to the groove 11 in thesense of providing a close fit. If the groove 11 is embodied as acircular bore, the cylindrical embodiment of the housing of the actuator26 suggests itself. To provide[as long as possible an actuating path “s”by the use of an actuator 26 utilizing the piezo effect ormagnetostriction, it is advantageous to select a structural shape of theactuator 26 wherein the length l26 of the actuator 26, which length l26extends in the same direction as the actuating path “s,” is clearlygreater than the actuator dimensions extending transversely to theactuator length l26. Thus, a ratio of the actuator length l26 to widthb26 of the actuator 26 is at least 2:1, and, in particular, is greaterthan 4:1, from which there results a longer, narrower structural shapeof the actuator 26. The effective direction and, corresponding to it,the installed position of the actuator 26, is always selected to bedirected in the same way as the intended displacement of the holdingdevice, or of the base body 22.

To achieve a longer actuating path “s” than can be generated by a singleactuator 26, it is also possible to connect two or more, preferablyidentical actuators 26 in series, wherein only the actuator 26, which islocated the farthest from the holding device 18 to be displaced, or fromthe base body 22 to be displaced, is rigidly connected with the groove11. With the remaining actuators 26, a base element 28 of the nextfollowing actuator 26 is rigidly connected with the head element 27 ofthe previous actuator 26, so that the actuating paths “s” of theserially arranged actuators 26 can be added together when an electricalcontrol signal US is simultaneously applied to the several seriallyarranged actuators 26.

By displacing the holding device 18, or the base body 22, in the groove11 by the operation of a controllable actuating device 26, or actuator26, it is possible to laterally displace a dressing 02, which has beenapplied to the cylinder 01 and which dressing 02 is held in place by theholding device 18. The controllable actuating device or actuator 26 canbe operated by remote control, for example from a control console, whilethe printing process is running. In other words, the actuator 26 can beoperated without a printing unit needing to be stopped. Because of thisremote control operation of actuator 26, the position of the dressing02, and therefore the printed image printed by it, can be aligned asneeded in relation to the material 24 to be imprinted, which material 24is stretched laterally or is fanned out in the direction Q, as seen inFIG. 1, in relation to the production direction P of the cylinder 01, orin relation to other print positions. Such lateral alignment of thedressing 02, through the operation of actuator 26 is done for thepurpose of obtaining an improved indexing, as well as improved side andcircumferential registration. If, in the course of the material 24passing through the printing unit, the lateral extension Q of thematerial 24 to be imprinted changes from one print position to afurther, subsequent print position, the actuating path “s,” which isshown in FIG. 3 and which is provided by an actuating device 26, oractuator 26 arranged there in a cylinder 01, can be of differentdimensions, for example can be longer from one print position to thenext.

Several dressings 02, preferably from two to six dressings 02, can alsobe arranged in the axial direction of the cylinder 01, so that thecontrollable actuating device 26, or the actuator 26, can be utilizedfor changing a distance between two, preferably adjoiningly arranged,dressings over an actuating path “s,” which path is oriented axially, inrespect to the cylinder 01. It is advantageous, in accordance with thepresent invention if the at least one actuator 26 arranged in the groove11, or the at least one controllable actuating device 26 arranged in thegroove 11, displaces the two dressings 02 affected by the distancechange simultaneously and in the same way over an actuating path “s”oriented axially with respect to the cylinder 01. It can also beprovided that at least one actuator 26, or at least one controllableactuating device 26, and positioned in the groove 11, is assigned toeach one of the dressings 02, which dressings 02 are arranged in theaxial direction of the cylinder 01 on its surface area 09. If twogrooves 11, which are arranged offset with respect to each other in thecircumferential direction of the cylinder 01, are provided on a cylinder01, at least one actuator 26, or at least one controllable actuatingdevice 26, can be arranged in each groove 11. At least one holdingdevice 18, for example, is assigned to each dressing 02, which maintainsthe dressing 02 on the surface area 09, wherein the actuator 26, or thecontrollable actuating device 26, changes a position of the holdingdevice 18 holding the dressing 02 in the axial direction of the cylinder01.

It is furthermore advantageous to provide a linear measuring system,which is configured as a DMS, or wire strain gauge full bridge, and tointegrate it, for example, into the housing of the actuator 26 for usein determining the actuating path “s” provided by the actuator headelement 27. The measurement result of such a linear measuring system isthen transmitted, for evaluation, to a location outside of the cylinder01, for example to a control console of the printing unit. The locationof the printed image, or of reference markers, on the material to beimprinted 24 can be detected by the use of a sensor, which is directedonto the material 24 to be imprinted for determining an intendedposition of a printed image which had been imprinted at different printpositions, for example by the use of an image sensor and, in particulara CCD camera. It is then possible to construct a regulating device,which corrects, as required, the actuating path “s” provided by thecontrollable actuating device 26 to the holding device 18 in the axialdirection of this cylinder 01 by a comparison of the detected positionof the printed image with the intended position of the printed image.

While a preferred embodiment of a cylinder of a web-fed printing pressand of a printing unit, in accordance with the present invention hasbeen set forth fully and completely hereinabove, it will be apparent toone of skill in the art that various changes in, for example, the drivefor the cylinders, a source of supply of the material to be printed, andthe like could be made without departing from the true spirit and scopeof the present invention which is accordingly to be limited only by thefollowing claims.

1-41. (canceled)
 42. A cylinder of a printing press comprising: at leastone cylinder groove beneath a surface of said cylinder, said cylindergroove extending axially in said cylinder; at least one dressing endholding device in said cylinder groove and adapted to hold an end of adressing supported on said surface of said cylinder; and a controllableactuator in said cylinder groove and adapted in response to a controlsignal applied to it, to change its length axially in said cylindergroove, said controllable actuator being in operative contact with saidholding device to displace said holding device axially over an actuatingpath oriented axially in said cylinder.
 43. The cylinder of claim 42further including at least first and second dressings arranged in saidaxial direction on said cylinder surface.
 44. The cylinder of claim 43wherein said controllable actuator is operable to change a spacingdistance between said at least first and second dressings over saidactuating path.
 45. A cylinder of a printing press comprising: at leastone cylinder groove extending axially beneath a surface area of saidcylinder; at least first and second dressings supported on said surfaceand arranged in an axial direction of said cylinder; and at least oneactuating means in said cylinder groove and usable to change a distancebetween said at least first and second dressings over an actuating pathoriented in said axial direction of said cylinder, said at least oneactuating means being electrically operable.
 46. The cylinder of claim45 wherein said actuating means is an electric motor.
 47. The cylinderof claim 45 further including a control signal applied to said actuatingmeans, said actuating means having a changeable axial length, saidcontrol signal causing said actuating means to change its axial lengthto change said distance between said first and second dressings oversaid actuating path.
 48. The cylinder of claim 43 wherein said at leastfirst and second dressings are arranged next to each other on saidcylinder.
 49. The cylinder of claim 45 wherein said at least first andsecond dressings are arranged next to each other on said cylinder. 50.The cylinder of claim 43 further including a separate actuator assignedto each of said first and second dressings.
 51. The cylinder of claim 45further including a separate actuating means arranged to each of saidfirst and second dressings.
 52. The cylinder of claim 42 furtherincluding a second cylinder groove offset from said first cylindergroove in a circumferential direction of said cylinder and at least onesaid actuator in each said groove.
 53. The cylinder of claim 45 furtherincluding a second cylinder groove offset from said first cylindergroove in a circumferential direction of said cylinder and at least onesaid actuating means in each said groove.
 54. The cylinder of claim 43further including at least one holding device for each of said first andsecond dressings, said actuator changing a position of each said holdingdevice.
 55. The cylinder of claim 45 further including at least oneholding device for each of said first and second dressings, saidactuating means changing a position of each said holding device.
 56. Aprinting group comprising: a plurality of print positions, each saidprint position having printing cylinders adapted to print color pointsof a common printed image on a material to be printed, said material tobe printed passing through serial ones of said print positions in adirection of travel and being subject to a lateral extension changingtransversely to said direction of travel; at least one dressing on eachof said printing cylinders and adapted to print said color points ofsaid common printed image; at least one axially extending groove beneatha surface area of each said printing cylinder, said at least one groovehaving a slit-shaped opening extending to said cylinder surface; atleast one holding device in each said groove and engageable with adressing end extending from a dressing on said cylinder surface intosaid cylinder groove through said slit-shaped opening; and an actuatingmeans in said at least one groove in at least one of said printingcylinders, said actuating means being usable to displace said at leastone holding device in said cylinder axial direction over an actuatingpath in response to a control signal applied to said actuating means,whereby said at least one dressing arranged on said at least oneprinting cylinder at said print position is adjusted in its axialposition such that said printed color points of said common printedimage are axially positioned correctly in accordance with said lateralextension of the material to be imprinted.
 57. The printing unit ofclaim 56 wherein said actuating means is an actuator.
 58. The printingunit of claim 57 wherein said actuator changes axial length with respectto said cylinder in response to said control signal.
 59. The printingunit of claim 56 wherein said actuating means moves said holding deviceduring operation of said printing unit.
 60. The printing unit of claim56 wherein said actuating means is located in said grooves in at leastone of a forme cylinder and a transfer cylinder.
 61. The printing unitof claim 56 further including a linear measuring system.
 62. Theprinting unit of claim 61 wherein said linear measuring system is a wirestrain gauge in said actuating means.
 63. The printing unit of claim 61further including means for transmitting a measurement obtained by saidlinear measuring system outside of said cylinder.
 64. The printing unitof claim 56 further including a print image detector in said printingunit and usable with said actuating means for positioning said printedimage.
 65. The printing unit of claim 64 wherein said print imagedetector is a sensor directed onto the material to be printed.
 66. Theprinting unit of claim 65 wherein said sensor is an image sensor. 67.The printing unit of claim 66 wherein said image sensor is a CCD camera.68. The printing unit of claim 56 further including a regulating deviceincluding means for comparing said common printed image with a referenceprinted image and means for controlling said actuating means in responseto said comparison.
 69. The printing unit of claim 68 further includinga control console for said printing unit, said regulating device beingarranged in said control console.
 70. The cylinder of claim 42 whereinsaid control signal is an electrical control signal.
 71. The printingunit of claim 56 wherein said control signal is an electrical controlsignal.
 72. The cylinder of claim 42 wherein said actuator performs atranslatory movement for displacing said holding device.
 73. Theprinting unit of claim 56 wherein said actuating means performs atranslatory movement for displacing said holding device.
 74. Thecylinder of claim 42 wherein said actuator has a length and a width,said length being greater than said width.
 75. The cylinder of claim 45wherein said actuating means has a length and a width, said length beinggreater than said width.
 76. The printing unit of claim 56 wherein saidactuating means has a length and a width, said length being greater thansaid width.
 77. The cylinder of claim 42 wherein said actuator has anactuator length and an actuator width and wherein a ratio of saidactuator length to said actuator width is greater than
 2. 78. Theprinting unit of claim 57 wherein said actuator has an actuator lengthand an actuator width and wherein a ratio of said actuator length tosaid actuator width is greater than
 2. 79. The cylinder of claim 42wherein said actuating path is between 100 um and 2 mm.
 80. The cylinderof claim 45 wherein said actuating path is between 100 um and 2 mm. 81.The printing unit of claim 56 wherein said actuating path is between 100um and 2 mm.
 82. The cylinder of claim 42 wherein said actuator is oneof a piezo-electrical system and a magnetostrictive system.
 83. Theprinting unit of claim 57 wherein said actuator is one of apiezo-electrical system and a magnetostrictive system.
 84. The cylinderof claim 42 wherein said actuator is remotely controllable.
 85. Thecylinder of claim 45 wherein said actuating means is remotelycontrollable.
 86. The printing unit of claim 56 wherein said actuatingmeans is remotely controllable.
 87. The cylinder of claim 42 whereinsaid actuator includes a housing, said housing being adapted to a shapeof said at least one cylinder groove.
 88. The cylinder of claim 45wherein said actuating means includes a housing, said housing beingadapted to a shape of said at least one cylinder groove.
 89. Theprinting unit of claim 56 wherein said actuating means includes ahousing, said housing being adapted to a shape of said at least onecylinder groove.
 90. The cylinder of claim 42 wherein said actuatorincludes a head element and a base element, said head element beingrigidly connected with said groove, said head element exerting a forceon said holding device for moving said holding device.
 91. The printingunit of claim 57 wherein said actuator includes a head element and abase element, said head element being rigidly connected with saidgroove, said head element exerting a force on said holding device formoving said holding device.
 92. The cylinder of claim 42 wherein saidholding device includes at least one plate end holding element and aspring.
 93. The printing unit of claim 56 wherein said holding deviceincludes at least one plate end holding element and a spring.
 94. Thecylinder of claim 92 wherein said holding element is a plate endclamping piece.
 95. The printing unit of claim 93 wherein said holdingelement is a plate end clamping piece.
 96. The cylinder of claim 92wherein said holding element is a registration pin.
 97. The printingunit of claim 93 wherein said holding element is a registration pin. 98.The cylinder of claim 42 further including a base body in said cylindergroove, said holding device being positioned in said base body, saidactuator displacing said base body.
 99. The printing unit of claim 57further including a base body in said cylinder groove, said holdingdevice being positioned in said base body, said actuator displacing saidbase body.
 100. The printing unit of claim 42 further including aplurality of said controllable actuators in said groove and including afirst actuator located remote from said holding device and a secondactuator being said actuator in contact with said holding device, saidfirst actuator being rigidly connected to said groove, a remainder ofsaid plurality of actuators being connected with each other, saidactuating paths of said plurality of actuators being cumulative.